Tufting machines



United States Patent 2,707,446 5/1955 McCutchen 1 12/79 2,818,03712/1957 McNutt 112/79 2,840,019 6/1958 Beasley 112/79 3,006,296 10/1961Penman... 1 12/79.6 3,221,682 12/1965 Burne1l.... 1 12/79 3,380,4144/1968 Gray 112/79 3,442,233 5/1969 Card 1 12/79 Primary Examiner-JordanFranklin Assistant Examiner-George V. Larkin Attorneys-Marshall J.Breen, Chester A. Williams and Julian Falk ABSTRACT: In order tominimise or eliminate stopmarking in a tufted product during themanufacture thereof on a tufting machine it is proposed to provide anauxiliary drive means whereby the puller rolls may be drivenindependently of machine operation during periods of machine stoppage tokeep the yarn under tension and avoid withdrawal or retraction thereof.

PATENTEDUECZZIHYU 3,548,766

' SHEET 1 0F 2 INVENT Clifford Colbert ATTORNEY rur'rmc MACHINES Theinvention concerns tufting machines and has more particular reference toan attachment therefor whereby the incidence of stop marking is reduced.

Prolonged stoppage of a tufting machine, which stoppage may be due toone of several operational reasons, may, depending upon the type of pileyarn concerned, give rise to a withdrawal of yarn from loops or tuftsalready formed in a backing fabric with the result that a line of tuftseach of a reduced height relative to the intended height will be presentin the finished product and as a fault therein. The problem is ofparticular importance if the pile yarn is a bulked filament yarn since,on machine stoppage, the yarn present between the tufting needles andthe next adjacent point at which the yarn is positively held retracts,and thus draws yarn from the last inserted loops.

The primary object of the present invention is to provide a meanswhereby the incidence of marking is reduced or the effects thereofminimised.

According to the present invention a tufting machine has a first yarnfeed means actuablc to supply yarn at a required rate according to apredetermined sequence, and a second yarn feed means spaced therefrom inthe direction of yarn feed and from which the yarns pass to thetuftingneedles, the first and second said means normally being operablein synchronism with the tufting machine operation to supply yarn to thetufting machine, and an auxiliary drive adapted independently of machineoperation to drive the said second feed means and thus to maintain atension in the yarn between the first and second feed means therefor andto prevent reverse motion of the yarn at the said second feed means.

The invention will now be described further, by way of example only,with reference to the accompanying drawings which illustrate oneembodiment thereof and in which:

FIG. 1 is a diagrammatic side elevation of a tufting machine embodyingthe invention; p

FIG. 2 is a front elevation of one end of the machine shown in FIG. 1;and 7 FIG. 3 is a cross section taken throughthe freewheel arrangementin the drive transmission of the puller rolls.

Thus, referring now to the drawings, and particularly to FIG. 1 thereof,each pile yarn 11 passes from a creel (not shown) around the drivenrollers 12a of a patterning attachment 12, through a tube element 13a ofa tube bank 13, thence to a pair of puller rolls l4, and on to thetufting machine needles l5.

The feed of yarn is controlled by the rollers 12a of the patterningattachment in known manner, a quantity of yarn sufficient for theformation of a loop, or a lesser quantity of yarn as appropriate, beingdelivered to the needle at each machine cycle, according to patternrequirements.

The puller rolls 14 are of the kind disclosed in prior British PatentSpecification No. 916,937 and comprise a pair of corrugated rolls havingintenneshing teeth of uniform depth between which the yarn passes. Therolls are so spaced from each other that the clearance between thecrests and the roots of the interrneshing teeth is greater than thethickness of the yarn so as to allow slippage of the yarn, and one ofthe rolls is normally driven at a speed greater than that at which yarnis fed to the pair of rolls.

The patterning attachment 12a and the puller rolls 14 are driven fromthe main shaft 16 of the tufiing machine in the usual way and thus theirmotion is dependent upon the motion of such main shaft. Any stoppage ofthe mainshaft, that is to say of the tufting machine, is accompanied bya stoppage of the patterning attachment and of the puller rolls.

In accordance with the present invention the puller rolls are providedalso with an auxiliary drive means l7-independent of the main shaft 16and adapted to beoperable to drive the puller rolls 14 on machinestoppage. The auxiliary drive means 17 is best shown in FIGS. 1 and 2and will be seen to comprise an auxiliary drive motor 18, an auxiliaryshaft 19 to ranged in spaced parallel disposition relative to the mainshah 16, a sprocket 20 carried on the auxiliary shafl, a free wheelassembly 21 mounted on the main shaft, and drive chains 22, 23 betweenthe sprocket 20 and the free wheel assembly 21 and between such assembly21 and a sprocket on the puller rolls 14 respectively.

Sprocket 20 on the auxiliary shaft 19 is coupled to the shaft through aconventional unidirectional clutch arranged to allow such sprocket tooverrun the shaft when necessary.

The free wheel assembly 21, see particularly FIG. 3, comprises coaxiallyarranged inner and outer elements 21a, 21b having roller wedges 21ctherebetween, the inner such element being keyed to the main shah, as at24, and the outer element carrying spaced sprockets 25, 26 arrangedrespectively to engage the drive chains 22, 23. The free wheel assemblyis adapted and arranged to transmit a drive from the main shaft 16 tothe outer element 21b on motion of the former in the forward drivedirection thereof and to permit of a motion of the outer element in suchforward direction relative to the inner element, in a manner well known,a wedging action of the roller edges relative to inner and outerelements ensuring the drive transmission when appropriate.

A drive is applied to the main shaft 16 from a main drive motor 27 viadriving chains or belts 28, such chains or belts extending aroundsprockets 29, 30 secured respectively to the output shaft 31 of themotor 27 and the said main shaft.

In operation, upon machine stoppage the auxiliary drive means 17 isactuated and the puller rolls 14 are caused to con tinue to rotate todraw the yarn ll forwardly from the patterning attachment 12, the drivetransmission being from auxiliary motor 18 via the auxiliary shaft 19 tosprocket 20 and then to the outer element 21b of the free wheelassembly. From such outer element the drive passes to the puller rollsvia chain 23. As, upon machine stoppage, the yarn is effectively stoppedat the patterning attachment 12, the puller rolls 14, which rollscontinue to rotate due to the drive from the auxiliary means, merelyslip on the yarn thereby maintaining such yarn under tension andpreventing the retraction of the yarn beyond the puller rolls in adirection against the direction of feed of the yarn. Any retraction ofthe yarn is a retraction of the length of yarn between the puller rollsand the needles, and having regard to the comparatively short length ofyarn involved the amount of retraction, and thus the extent ofwithdrawal, is small.

During normal machine operation the auxiliary drive motor will beineffective in driving the puller rolls, the drive trans mission fromthe main drive motor to the puller rolls being through the free wheelassembly, sprocket '20 overrunning the shaft on which it is supported.Whilst it may well be found convenient to arrange that the auxiliarymotor will be switched on only on machine stoppage, in somecircumstances it may be found preferable to have the auxiliary motorrotate continuously so long as the speed thereof does not exceed that ofthe main drive motor.

If desired, the conventional yarn jerker assembly can be modified toreduce the yarn path length between the puller rolls and the needles. Byfollowing this particular course, the possibility of any yarn withdrawalsuch as might occur on machine stoppage manifesting itself as a fault inthe finished product is reduced or even eliminated. The modification ofthe yarn jerker is simple and will usually involve making collapsiblethe fixed part of such jerker, the said part, for example, being mountedon air cylinders or by a mechanical linkage to achieve this purpose.

A tufting machine having a yarn jerker modified as above will beprovided with a prepositioned stop device to ensure that the needle barand jerker always come to rest in the same position. i

The invention is not restricted to the exact features of the embodimenthereinbefore described since alternatives will readily presentthemselves to one skilled in the art. Thus, for example, the pullerrolls may be replaced by an equivalent structure intended to achieve aforwarding of the yarn from a which the output of the said motor iscoupled and which is aryarn feed means.

I claim:

1. A tufting machine including needles operable for penetrating a basefabric to form a pile and yarn feed means for feeding yarn to saidneedles, said yarn feed means including a first .yarn feed meansactuable to supply yarn at a required rate in accordance with apredetermined sequence, a second yarn feed means spaced from said firstyarn feed means in thedirection of yarn feed and from which the yarnspass to said needles, said first and second yam feed means beingoperable in synchronism with said tufting machine to supply yarn to saidtufting machine, and auxiliary drive means operable independently of themain drive means of said tufizing machine for driving said second yarnfeed means to maintain a tension in the yarn between said first andsecond yarn feed means and to prevent reverse motion of the yarn at saidsecond yarn feed means.

2. A tufting machine as claimed in claim 1, further characterized by anunidirectional coupling member in the transmission of the auxiliarydrive means adapted to allow the second yarn feed means to overrun theauxiliary drive means when the latter is inoperative.

3. A tufting machine as claimed in claim 2 wherein the auxiliarydrivemeans comprises a drive motor, an auxiliary shaft drivinglyconnected to such motor for rotation thereby, a freewheel assemblymounted on the machine main shah and coupled thereto, the unidirectionalcoupling member being on the auxiliary shaft, a drive transmissionmeansbetween the said coupling member and the freewheel assembly, and afurther drive transmission means between such assembly and the secondfeed means, the freewheel assembly including an inner element rotatablewith the main shah, an outer element arranged coaxially with the innerelement and radially outwardly thereof, roller wedges disposed betweenthe inner and outer elements, and input and output sprockets on the saidouter element, the said input sprocket receiving the first drivetransmission means aforesaid and the said output sprocket receiving thesaid further drive transmission means, the whole being adapted andarranged to transmit a drive from the drive shaft to the output sprocketor from the auxiliary motor to such sprocket according to whichever isthe higher of the auxiliary drive and main drive speeds.

4. A tufting machine as claimed in claim 1 wherein the second yarn feedmeans comprises a pair of cooperating corrugated rolls between which theyarns pass.

